1. Field of the Invention
The present invention relates to a hand-written signature authentication program, method, and apparatus capable of improving the matching precision by preprocessing or postprocessing matching data of hand-written signature.
2. Description of the Related Art
Conventionally, an authenticating method based on the amount of the feature of a hand-written signature is well known as one of the biometrics authenticating methods (of authenticating a user based on the physical features of a person such as a fingerprint, a retina, an iris, a voice print, etc. when the person is accessing a network or activating a personal computer). In this case, a matching check is carried out by comparing the amount of the feature in the shape of handwriting, writing speed, writing acceleration, writing pressure, etc. between a hand-written signature placed when it is registered and a hand-written signature placed when the user is to be authenticated.
FIG. 1 shows the conventional authentication system based on hand-written signatures. In FIG. 1, an authentication system 1 first inputs ‘’ (‘Fujitsu Taro’) which is a signature 4 in Japanese characters, or ‘Fujitsu’ which is a signature 4′ in English characters with an exclusive pen not shown in the attached drawings into a handwriting input device 3 connected to a data input display device 2.
Then, the information obtained from the signature 4 or 4′ is registered in, for example, a host equipment 5 of a large computer, etc. The information obtained from the signature 4 or 4′ can be the shape of handwriting, writing speed, writing acceleration, writing pressure, etc.
When a person named  (Fujitsu Taro) or Fujitsu is to be authenticated, the person inputs again  (Fujitsu Taro), the hand-written signature 4 in Japanese characters, or Fujitsu, the hand-written signature 4′ in English characters, into the handwriting input device 3 of the data input display device 2 as described above. The information about the shape of handwriting, writing speed, writing acceleration, and writing pressure of the signature 4 or 4′ is given to the host equipment 5. Then, the host equipment 5 compares the shape of handwriting, writing speed, writing acceleration, and writing pressure of the registered hand-written signature with the shape of handwriting, writing speed, writing acceleration, and writing pressure of the just input hand-written signature, and notifies the data input display device 2 of the matching/non-matching result.
In this case, the amount of the feature of the above mentioned shape of handwriting, writing speed, writing acceleration, and writing pressure has been conventionally represented by numeric values by computing the similarity between the amount of the feature obtained at the time of registration and the amount of the feature obtained at the time of application for authentication. The matching/non-matching result is determined using the total values of the amounts of features according to the common comparison logic.
However, since a hand-written signature is biometrics information, the feature appearing in the amount of the feature depends on each person, that is, each person has his or her own amount of the feature. Therefore, in the conventional common comparison logic for evaluation based on the total value of similarity with the amount of the feature of respective writing components, the above mentioned different features depending on each person are ignored, thereby failing in obtaining the optimum comparison result for each person. As a result, a person to be authenticated can be mistakenly rejected, or a wrong person can be mistakenly authenticated.